9.12 Ligament Sprains (Including Joint Capsule Injuries)

Presentation

A joint is distorted beyond its normal anatomical limits (as
when an ankle is inverted or a shoulder is dislocated and
reduced) The patient may complain of a snapping or popping
noise at the time of injury, immediate swelling, and loss of
function (suggestive of second- or third-degree sprain or a
fracture); or he may corne in hours to days following the
injury, complaining of gradually increasing swelling and
resulting pain and stiffness (suggestive of a first- or
second-degree sprain and development of a traumatic
effusion).

What to do:

Obtain a detailed history of the mechanism of injury, and
examine the joint for structural integrity, function, and
point tenderness. Use the uninjured limb as a control.

Obtain x rays (these can be deferred if necessary).

With first-degree and second-degree sprains, gently
immobilize the joint using an elastic bandage alone, or in
combination with a cotton roll and/or plaster splint, as
discomfort demands.

Consider prescribing anti-inflammatory pain medication when
the patient complains of pain at rest and provide crutches
when discomfort will not allow weight bearing.

If there is a fracture or ligament tear with instability,
the limb is usually best immobilized in a splint or cast.
Splint ankles at 90 degrees, wrists in extension, fingers at
slight flexion.

Instrurt the patient in rest, elevation, and application of
ice (10-20 minutes each hour) for the first 24 hours.

Explain to the patient that swelling in acute
musculoskeletal injuries usually increases for the first 24
hours, and then decreases over the next 2-4 days (longer if
the treatment above is not employed) and that some swelling
and discomfort may persist for several weeks and at times
for several months

Explain the possibility of occult injuries, the necessity
for followups, and the slow healing of injured ligaments
(usually 6 months until full strength is regained).

What not to do:

Do not obtain x rays before the history or physical
examination. Films of the wrong spot can be very misleading.
For example, physicians have been steered away from the
diagnosis of an avulsion fracture of the base of the fifth
metatarsal by the presence of normal ankle films.

Do not base the diagnosis on x rays. They should be used
as confirmatory evidence.

Discussion

Ligamentous injuries are classified as first-degree,
(minimal stretching); second-degree (a partial tear with
functional loss and bleeding but still holding); and third-degree (complete tear with ligamentous instability, often
requiring a cast). A tense joint effusion will limit the
physical examination (and is one reason to require re-evaluation after the swelling has decreased) but also
suggests less than a third degree ligamentous injury, which
is normally accompanied by a tear of the joint capsule.